Commit 34eb2a52 authored by Zhaolei's avatar Zhaolei Committed by Chris Mason
Browse files

btrfs: Remove useless condition in start_log_trans() 



Dan Carpenter <dan.carpenter@oracle.com> reported a smatch warning
for start_log_trans():
 fs/btrfs/tree-log.c:178 start_log_trans()
 warn: we tested 'root->log_root' before and it was 'false'

 fs/btrfs/tree-log.c
 147          if (root->log_root) {
 We test "root->log_root" here.
 ...

Reason:
 Condition of:
 fs/btrfs/tree-log.c:178: if (!root->log_root) {
 is not necessary after commit: 7237f183

 It caused a smatch warning, and no functionally error.

Fix:
 Deleting above condition will make smatch shut up,
 but a better way is to do cleanup for start_log_trans()
 to remove duplicated code and make code more readable.

Reported-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: default avatarZhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: default avatarChris Mason <clm@fb.com>
parent 46cd2855

fs/btrfs/tree-log.c

+17 −26
Original line number Diff line number Diff line
@@ -140,34 +140,23 @@ static int start_log_trans(struct btrfs_trans_handle *trans, 
			   struct btrfs_root *root,

			   struct btrfs_log_ctx *ctx)

{

	int index;

	int ret;

	int ret = 0;



	mutex_lock(&root->log_mutex);



	if (root->log_root) {

		if (btrfs_need_log_full_commit(root->fs_info, trans)) {

			ret = -EAGAIN;

			goto out;

		}



		if (!root->log_start_pid) {

			root->log_start_pid = current->pid;

			clear_bit(BTRFS_ROOT_MULTI_LOG_TASKS, &root->state);

			root->log_start_pid = current->pid;

		} else if (root->log_start_pid != current->pid) {

			set_bit(BTRFS_ROOT_MULTI_LOG_TASKS, &root->state);

		}



		atomic_inc(&root->log_batch);

		atomic_inc(&root->log_writers);

		if (ctx) {

			index = root->log_transid % 2;

			list_add_tail(&ctx->list, &root->log_ctxs[index]);

			ctx->log_transid = root->log_transid;

		}

		mutex_unlock(&root->log_mutex);

		return 0;

	}



	ret = 0;

	} else {

		mutex_lock(&root->fs_info->tree_log_mutex);

		if (!root->fs_info->log_root_tree)

			ret = btrfs_init_log_root_tree(trans, root->fs_info);
@@ -175,20 +164,22 @@ static int start_log_trans(struct btrfs_trans_handle *trans, 
		if (ret)

			goto out;



	if (!root->log_root) {

		ret = btrfs_add_log_tree(trans, root);

		if (ret)

			goto out;

	}



		clear_bit(BTRFS_ROOT_MULTI_LOG_TASKS, &root->state);

		root->log_start_pid = current->pid;

	}



	atomic_inc(&root->log_batch);

	atomic_inc(&root->log_writers);

	if (ctx) {

		index = root->log_transid % 2;

		int index = root->log_transid % 2;

		list_add_tail(&ctx->list, &root->log_ctxs[index]);

		ctx->log_transid = root->log_transid;

	}



out:

	mutex_unlock(&root->log_mutex);

	return ret;

CRA Git | Maintained and supported by SUSTech CRA and CCSE